Sept. 13 (UPI) -- Human rights experts called on India's government Wednesday to protect reporters after a prominent journalist and human rights advocate was killed this month.

Guari Lankesh, 55, was shot dead outside of her home on Sept. 5, and was later found dead on her veranda with bullet wounds to her head and chest. At least three suspects were involved, according to police.

"We urge the authorities in India to take active steps to reverse a political climate that in recent years have become increasingly polarized and hostile, especially to the media and those exercising the freedom of expression," three experts said Wednesday.

"The murder of Gauri Lankesh is a terrible and painful tragedy for all who knew and loved her and her work, and is a vicious attack on the freedom of the press in India, which we unequivocally condemn."

"Governments have a responsibility to build a safe environment for independent voices, including those of journalists critical of the authorities," they added.

Lankesh's was India's fourth death in the last three years of activists who had opposed the rise of Hindu fundamentalism in politics, the U.N.'s Office of the High Commissioner for Human Rights said.

The experts' letter was signed by David Kaye, an expert on freedom of opinion and expression; Agnes Callamard, on summary or arbitrary executions; and Michel Forst, on the situation of human rights defenders.

The panel was appointed by the Geneva-based Human Rights Council to examine and report back on a specific human rights theme or a country situation. They are not paid and are not members of U.N. staff.

"The Indian authorities should unequivocally condemn the killing of Gauri Lankesh, investigate it, bring all the perpetrators -- including the masterminds -- to account, and take seriously the safety of journalists," they said.

Lankesh was characterized by the experts as a "rationalist," a term used to describe people in Indian who are against the use of religion in politics.

Last November, Lankesh was sentenced to six months imprisonment for defaming two politicians of the ruling party. She was released on bail during the appeals process.

"India cannot afford to go on creating victims of hatred and intolerance," the experts concluded. "We urge the authorities to take steps to ensure a culture of diversity, in which everyone, including an independent media, can be safe to express their opinions."

Karnataka home minister Ramalinga Reddy said Wednesday "nothing has been revealed so far" in the investigation by a Special Investigation Team. On Sunday, Reddy said the team had gathered "some clues" in connection with the case and has offered a reward.

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